It is important that before an assessment is used, we understand what and why we are assessing. This is something that I have to do more. Often, I use assessment for judgement purposes and I realise that I need to make sure that the assessment is correctly designed for the intended measure.

Yes I find the three levels of purpose useful, especially the impact. Assessments that facilitate the pupils to reflect on their learning and self-assess, can aid them to self-manage their learning for optimum progress. 

We do NFER end of term assessment for Maths, SPAG and reading and through gap analysis, we are able to find the areas of improvement. However, this sometimes happens too late in the term and their impact is sometimes lost. I think that short mid-term assessments will have more impact and won't make the gap analysis too tedious as well. Once pupils self-assess in the mid-term assessment, they can show more progress in the end of term assessments.

Knowing the purpose of an assessment is essential for both its creation (e.g. ensuring the form suits the purpose), but also how it is interpreted. It will also potentially affect the measures put in place regarding reliability (e.g. If it is a key summative assessment that may affect coursework marks, or setting, then blind-marking to avoid bias might be appropriate. This would be less practicable if the purpose was the determine understanding of a threshold concept and how the teacher may need to adapt future lessons to address this).

It is a useful way of breaking down the broader idea of purpose.

At present, our essay-based (or story/transactional) writing tasks are the main type used for summative assessments. These both provide us with information on student understanding, but also are used for other purposes (e.g. interventions,...). We have started to incorporate more granular approaches (e.g. assessing for key concepts, vocabulary, reading level/age) as well, as this offers more targeted information on particular skills.

During the academic year we can often get so wrapped up in day to day life and data expectations we often forget to think about why we are doing the assessment in the first place, this is additionally evident when assessments have been premade and have not been revisted since tey were made. I fiind assessments such as exit tickets whilst time consuming to mark (if students are unable to mark them themselves) a useful tool to reflect and change the next lesson accordingly. 
The fundamental aim to enhance students learning and assessment is a vital tool in this. 

I think this is a really useful reflection tool when creating an assessment but also when planning lessons. It allows the teacher to really think about questionning not only written but verbal too.

What assessments do you do at school which have many purposes? Do you consider them to be overloaded? Why or why not?
At school we complete termly maths and reading assessment. These assessment are used to gather data on attainment for the teacher, trust and governs, they are also used to show progress in performance management reviews and they are supposed to be used to show gaps that teachers should then plug. However, these tests are often testing children on content that has not be taught so as they are tested thought out they look like they are making continued progress purely because they are learning more content. I think that this type of tests is overloaded and is not really achieving any of the outcomes that the school really want to use it for.